Friday, January 20, 2012

WCF-4 Client/Host quick start/tutorial

For those of you who already know WCF basics and need to start quickly here are guidelines to start a working client-server/service project:

My Quickest Start
  1. Designing Service Contracts
    1. Start simple, grow in time.
  2. Implement the contract
  3. Host the service - Console (starting simple).
    1. http://msdn.microsoft.com/en-us/library/ms731758.aspx
      1. New 'Console Application'
      2. See 'Example Host Code' below...
        1. Add Reference.... Select System.ServiceModel
        2. Reference 'ServiceModel'
        3. Start the service code
          1. Using
          2. Open
          3. Close
  4. Disable WcfSvcHost (if needed)
    1. "Right-click the WCF Service Project in Solution Explorer, choose Properties, and click WCF Options tab. The Start WCF Service Host when debugging another project in the same solution check box is enabled by default."
  5. CLIENT SIDE - Obtain the Service Contract, Bindings, and Addresses
    1. Enable the service
      1. Set the Host as the default startup program and run in without debugger (usually <CTRL>+F5).
    2. 'Add Service Reference...' 
      1. Past the service address in the 'Address' field and 'Go'.
      2. Point the service and 'OK' =results=> a new client proxy code will be generated in your client.
    3. SET YOUR CLIENT APPLICATION AS THE STARTUP PROGRAM :)
    4. Add service usage code to your client (see 'Example Client Code' below...).
  6. Run and relax :-).

    Example Host Code
    Code Snippet
    1. using System;
    2. using System.Collections.Generic;
    3. using System.Linq;
    4. using System.Text;
    5.  
    6. using System.ServiceModel;
    7. using System.ServiceModel.Description;
    8. using MyWcfLib;
    9.  
    10.  
    11. namespace MyServer
    12. {
    13.     class Program
    14.     {
    15.         static void Main(string[] args)
    16.         {
    17.             Uri baseAddress = new Uri("http://localhost:9090/hello");
    18.  
    19.             using (ServiceHost host = new ServiceHost(typeof(MyService), baseAddress))
    20.             {
    21.                 // Enable metadata publishing.
    22.                 ServiceMetadataBehavior smb = new ServiceMetadataBehavior();
    23.                 smb.HttpGetEnabled = true;
    24.                 smb.MetadataExporter.PolicyVersion = PolicyVersion.Policy15;
    25.                 host.Description.Behaviors.Add(smb);
    26.  
    27.                 // Open the ServiceHost to start listening for messages. Since
    28.                 // no endpoints are explicitly configured, the runtime will create
    29.                 // one endpoint per base address for each service contract implemented
    30.                 // by the service.
    31.                 host.Open();
    32.  
    33.                 Console.WriteLine("The service is ready at {0}", baseAddress);
    34.                 Console.WriteLine("Press <Enter> to stop the service.");
    35.                 Console.ReadLine();
    36.  
    37.                 // Close the ServiceHost.
    38.                 host.Close();
    39.             }
    40.  
    41.         }
    42.     }
    43. }

    Example Client Code
    Code Snippet
    1. using System;
    2. using System.Collections.Generic;
    3. using System.Linq;
    4. using System.Text;
    5.  
    6. namespace ConsoleApplication1
    7. {
    8.     class Program
    9.     {
    10.         static void Main(string[] args)
    11.         {
    12.             var client = new ServiceReference1.MyServiceClient();
    13.  
    14.             Console.WriteLine(client.GenerateGuid().ToString());
    15.             client.Close();
    16.  
    17.             Console.ReadLine();
    18.         }
    19.     }
    20. }


    MSDN's 'Basic Programming Lifecycle'


    Please, post comments if you find errors.
    I'll fix them ASAP and others can enjoy a cleaner clode.

    Hope it helps...

    Saturday, January 7, 2012

    WPF, XAML: TreeView HierarchicalDataTemplate databinding to unknown XML/DataSource

    Problem description
    • I wish to bind my TreeView to a datasource.
    • The TreeView should build its child nodes dynamically (unknows childs in datasource).
    • Each node should display its data or (if no data) its element name.

    Solution
    You need to use and understand these parts:
    1. HierarchicalDataTemplate
      1. HierarchicalDataTemplate.Triggers
    2. Binding XPath

    Usage Example
    Just copy paste and start playing / reading each part's help.

    XAML
    Code Snippet
    1. <Window x:Class="TreeViewDataBinding.Window1"
    2.     xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    3.     xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    4.     Title="Window1" Height="300" Width="300">
    5.     <Window.Resources>
    6.         <HierarchicalDataTemplate x:Key="NodeTemplate" >
    7.  
    8.             <TextBlock x:Name="tbName" Text="?" />
    9.  
    10.             <HierarchicalDataTemplate.ItemsSource>
    11.                 <Binding XPath="child::node()" />
    12.             </HierarchicalDataTemplate.ItemsSource>
    13.  
    14.             <HierarchicalDataTemplate.Triggers>
    15.                 <DataTrigger Binding="{Binding Path=NodeType}" Value="Text">
    16.                     <Setter TargetName="tbName" Property="Text" Value="{Binding Path=Value}"/>
    17.                 </DataTrigger>
    18.                 <DataTrigger Binding="{Binding Path=NodeType}" Value="Element">
    19.                     <Setter TargetName="tbName" Property="Text" Value="{Binding Path=Name}"/>
    20.                 </DataTrigger>
    21.             </HierarchicalDataTemplate.Triggers>
    22.         </HierarchicalDataTemplate>
    23.  
    24.         <XmlDataProvider x:Key="xmlDataProvider"/>
    25.     </Window.Resources>
    26.     
    27.     <StackPanel>
    28.         <Button Click="Button_Click">Reload</Button>
    29.         
    30.         <TreeView
    31.             ItemsSource="{Binding Source={StaticResource xmlDataProvider}, XPath=*}"
    32.             ItemTemplate="{StaticResource NodeTemplate}" />
    33.     </StackPanel>
    34. </Window>

    Code behind
    Code Snippet
    1. using System.Windows;
    2. using System.Windows.Data;
    3. using System;
    4.  
    5. namespace TreeViewDataBinding
    6. {
    7.     public partial class Window1 : Window
    8.     {
    9.         public Window1()
    10.         {
    11.             InitializeComponent();
    12.         }
    13.  
    14.         private void Button_Click(object sender, RoutedEventArgs e)
    15.         {
    16.             var provider = (XmlDataProvider)this.Resources["xmlDataProvider"];
    17.             provider.Source = new Uri(@"Data\standard.xml", UriKind.Relative);
    18.         }
    19.     }
    20. }

    Additional files



    Performance
    I was able to load 100MB of xml data in around ~6 seconds first time, ~4 seconds from the second time.

    Testbench station
    • i7 (8 cores) @ 2.80GHz
    • 4.00GB RAM
    • 64-Bit OS, Win7 Pro.
    CPU & memory usage
    The CPU was at idle when i started, the RAM was at the base line.

    Results

    Resources

    Hope it helps.